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1

Electron paramagnetic resonance study of impurities and point defects in oxide crystals

Stefaniuk I.

Opto-Electronics Review

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2018

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Vol. 26, No. 2

81--91

EN

In this topic review the results of the X-band electron paramagnetic resonance (EPR) measurements of Mn, Co, Cr, Fe ions in YAlO₃ (YAP) crystals and Fe ions in LiNbO₃ (LNO) crystals and of chromium doped Bi₁₂GeO₂₀ (BGO) and Ca₄GdO(BO₃)₃ single crystals, are presented. It is well known that the oxide crystals (for example:YAP, LNO, BGO) are one of the most widely used host materials for different optoelectronic applications. The nature of point defect of impurities and produced in the oxide crystal after irradiation by bismuth ions and after irradiation by the ²³⁵U ions with energy 9.47 MeV/u and ﬂuency 5 × 10¹¹ cm⁻¹ is discussed. The latter is important for applications of these oxide crystal as laser materials.

2

Influence of L-threonine on the growth, structural, optical, mechanical and nonlinear optical properties of tartaric acid single crystal

Thilakavathi G., Arun Kumar R., Gunasekaran V.

Materials Science Poland

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2018

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Vol. 36, No. 4

630--637

EN

Single crystals of pure and L-threonine added tartaric acid (LT/TA), organic nonlinear optical (NLO) materials were grown from their respective aqueous solution by slow evaporation method. The crystalline nature of the grown crystals was confirmed by powder X-ray diffraction analysis (XRD). UV-Vis-NIR absorption and transmission spectra revealed that the lower cut-off wavelength was around 281 nm and the crystals exhibited high transmission over visible and near IR region. The presence of the functional groups such as O–H, C–H, C–O, C=O in the grown crystals was confirmed by FT-IR analysis. CHN analysis was carried out to confirm the presence of L-threonine in the grown crystals. Microhardness study on the crystals revealed that the hardness number Hv increased with the applied load. The growth pattern of the crystals were analyzed through etching analysis from which the etch patterns in the shape of 'step-triangle' were observed. The second harmonic generation (SHG) properties of pure and L-threonine doped tartaric acid crystals were confirmed by Kurtz-Perry powder technique.

3

Nowe zasady pomiaru drugiej harmonicznej światła (SHG) w materiałach o zróżnicowanej wartości podatności nieliniowooptycznej

Wojciechowski A.

Elektronika : konstrukcje, technologie, zastosowania

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2016

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Vol. 57, nr 11

71--74

PL

Opracowano nowe podejście do pomiaru zjawiska drugiej harmonicznej światła (SHG) polegające na rejestracji kinetyki czasowego opóźnienia maksimum przebiegu sygnału SHG względem maksimum sygnału fali fundamentalnej (FUN) oraz pomiar kinetyki SHG. Z analizy literaturowej wynika, że dotychczas najczęściej prowadzono pomiar efektywności przetwarzania SHG jako stosunek maksimum natężenia SHG do maksimum fali padającej. Nowe podejście dostarcza dodatkowych informacji o kinetyce obsadzenia poziomów pułapkowych w obszarach częściowo nieuporządkowanych badanych materiałów, które generują dodatkowy sygnał SHG. Istotnym jest to ze metoda ta może być stosowana do materiałów posiadających duży (do 5 rzędów) rozrzut efektywności SHG. Ustalono podstawowe parametry techniczne wpływające na efektywność drugiej harmonicznej światła. Ustalono że przy tej samej gęstości mocy promieniowania istnieje prawie odwrotnie proporcjonalna relacja pomiędzy czasem opóźnienia i efektywnością drugiej harmonicznej. Oprócz tego zbadano wpływ innych czynników na dokładność pomiarów. Podstawy teoretyczne są oparte na analizie hiperpolaryzowalności wielu materiałów. Wśród nich nanokompozyty, monokryształy, nanoproszki i inne.

EN

We developed a new approach to measuring the phenomenon of second harmonic of the light (SHG) involving the registration of the kinetics of the time delay of the maximum waveform SHG terms of maximum wave signal fundamental (FUN) and the measurement of the kinetics of SHG. The analysis of the literature shows that until now the mostly introduced measurement processing efficiency as the ratio of the maximum of SHG to the maximum of the incident wave. The new approach provides additional information about the kinetics of filling of the traps levels in areas partially disordered for the tested materials, which generate additional SHG signal. It is important that this method can be used for materials with large (up to 5 rows) dispersion of SHG efficiency. It was found that for the same power density of the radiation are inversely proportional relationship between the delay time and efficiency of the second harmonic. In addition, were examined the effect of other factors on the accuracy of the measurements. Theoretical foundations are based on the analysis of hyperpolarizabilities of many materials. Among these nanocomposites, single crystals, nanopowders and other.

4

Destrukcyjne oddziaływanie promieniowania UV z poszczególnych podzakresów widmowych na materiały optyczne

Hemka L., Piotrowski L.

Prace Instytutu Elektrotechniki

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2012

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Z. 256

37-46

PL

W artykule przedstawiono wyniki prac eksperymentalnych prowadzonych w celu zbadania procesów destrukcyjnego oddziaływania na materiały optyczne promieniowania UV z poszczególnych podzakresów widmowych (UVA, UVB, UVC). Zbadano i przeanalizowano zmiany w czasie współczynnika przepuszczania oraz parametrów barwowych trzech rodzajów filtrów barwnych Schotta, soczewki, okularów będących elementem wyposażenia kabiny solaryjnej oraz próbki szkła boro-krzemowego.

EN

The paper presents results of experimental work carried out to investigate the impact of destructive processes in UV optical materials from each sub-spectrum (UVA, UVB and UVC). Examined and analyzed the changes in time and the transmission factor of three types of parameters Kelvin Schott color filters, lenses, glasses that are part of indoor tanning equipment and samples cabs boro-silicateglass.

5

Metrologia kinetyki fotoindukowanych zmian absorbancji w nanokompozytach krystalicznych

Wojciechowski A., Kityk I. V.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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Vol. 52, nr 12

103-106

PL

Opracowano metodykę pomiarów fotoindukowanych zmian absorbancji w krystalicznych nanokompozytach oraz warstwach stymulowanych laserami o promieniowaniu ciągłym i impulsowym. Pokazano możliwość detekcji zmian absorbancji w czasie rzeczywistym z dokładnością do kilku cm⁻¹ przy ogólnym pochłanianiu rzędu, co najmniej 10⁻³ cm⁻¹, co ma istotny wpływ na parametry nieliniowo optyczne. Przeprowadzono analizę spektralną fotoidukowanej absorbancji w zakresie widma optycznego od 250 nm do 800 nm. Jako źródła promieniowania wykorzystano laser ciągły CW Nd:YAG (532 nm), diody laserowe oraz impulsowy laser, CO₂. Ustalono procesy relaksacji zmian fotoindukowanej transparencji w zależności od przerwy energetycznej, fizykomechanicznych właściwości materiału, ilości nanocząstek, ilości domieszek.

EN

The authors have proposed a method of precise measurements of photoinduced changes in crystalline nanocomposites. It was shown a possibility of detection of photoinduced absorption in the real time of illumination. It was shown a possibility of photoinduced absorpance with precision up to 10⁻³ cm⁻¹ which has an important influence on nonlinear optical parameters. An analysis of photoinduced-absorbed spectrum was carried out within the spectral range 250 nm to 800 nm. As a source of photoinducing beam we have used CW Nd:YAG laser (532 nm), diodes and pulsed CO₂ laser. The processes of relaxation for the photoinduced changes are studied versus the energy gap, physical mechanical properties, number of nanoparticles, number of domains.

6

Charakterystyki wzbudzeniowo-emisyjne nanometrycznych proszków tlenku cyrkonu domieszkowanych jonami itru, europu i prazeodymu

Mierczyk Z., Kałdoński G., Mierczyk J., Łojkowski W., Fidelus J. D., Opalińska A.

Biuletyn Wojskowej Akademii Technicznej

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2011

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Vol. 60, nr 1

7-14

PL

W pracy przedstawiono wyniki badań materiałów luminescencyjnych na osnowie dwutlenku cyrkonu, domieszkowanych jonami itru, europu i prazeodymu, przeznaczonych do nowoczesnych półprzewodnikowych źródeł światła białego. Przeprowadzono pomiary charakterystyk wzbudzeniowo-emisyjnych i wyznaczono podstawowe parametry optyczne luminoforów.

EN

In this paper we focus on high-impact luminescence of Eu²⁺ or Pr²⁺doped ZrO₂ nanocrystals stabilized by Y₂O₃. As a class of inorganic luminescent phosphor, wide-band gap ZrO₂ has received considerable attention because of its utility for existing and future optoelectronic devices as a suitable host for rare-earth ions. In the article were gathered Exciting-emitting spectra of nanocrystals obtained by the hydrothermal microwave-driven process are presented. All investigated characteristics indicate the usability of studied materials as red luminescent phosphors.

7

Materiały typu szkło-ceramika : nowe trendy w materiałach optycznych

Pisarski W.A.

LAB Laboratoria, Aparatura, Badania

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2007

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R. 12, nr 2

47-50

8

Ultrafast optical switching for polyarylates with allylic groups by Nd:YAG Sagnac interferometer

Ciolek R., Ratusznik G.J., Swillo R., Pura B., Zadrozna I., Piramidowicz R., Kaczorowska E., Zagorski A.

Optica Applicata

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2006

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Vol. 36, nr 2-3

381-387

EN

In this paper, an ultrafast optical switching for thin polymer films (polyarylans with allylic groups) is presented. It was realized using the Nd:YAG Sagnac interferometer. Investigated polymers appeared to be suitable candidates for elements of integrated optical telecommunication systems.

9

Raman investigation of hybrid polymer thin films

Gnyba M., Keranen M., Kozanecki M., Kosmowski B. B.

Materials Science Poland

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2005

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Vol. 23, No. 1

29--39

EN

Raman spectroscopic studies were carried out for hybrid polymer thin films prepared for photonic applications by the sol-gel technology. Our aims were to analyse the ability of the Raman method toestimate the efficiency of the main reactions of the sol-gel process and to provide information about the chemical composition of the films as well as their thickness, profile, and quality. The difficulties in measurement such as low level of Raman signals, difficulties in data analysis caused by the complex structure of the materials, and the influence of interfering signals, are discussed. The application of Raman microscopy for characterising films based on 3-glycidoxypropyl-trimethoxysilane (GPTS), methacryloxypropyltrimethoxysilane (MPTS), and 3-aminopropyl-trimethoxysilane (APTES) is presented. The efficiencies of reactions of inorganic and organic polymerisation were measured and their products have been identified. The influence of the excitation beam wavelength as well as the type of substrate on the Raman spectra was investigated. Moreover, two-dimensional Raman mapping enabled us to record the thickness profiles of the deposited structures and to detect their defects.

10

Raman investigation of sol-gel-derived hybrid polymers for optoelectronics

Gnyba M., Keranen M., Kozanecki M., Bogdanowicz R., Kosmowski B. B., Wroczyński P.

Opto-Electronics Review

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2002

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Vol. 10, No. 2

137-143

EN

A Raman spectroscopic study was carried out in order to investigate the synthesis process of organically modified silane (ORMOSIL) hybrid polymers. These materials were prepared for optoelectronic application, using the sol-gel technology. Our aim was to analyse the ability of Raman measurements to estimate the efficiency and correctness of particular stages of the technological process. To synthesise a hybrid for optical planar waveguides, denoted as GSiC, a system of 3-glycidoxypropyl-trimethoxysilane/methacryloxy-propyltrimethoxysilane (GPTS/ MPTS) was used as a precursor. To diagnose the first step – gelation – the Raman spectra of monomers and gel were recorded. Analysis showed that gelation parameters should be improved to in-crease the efficiency of monomers hydrolysis and epoxy ring opening in GPTS. After next two steps – deposition and hardening – Raman microscopy was used for the characterisation of polymer thin films. Information about the film thickness, open-ing of double C=C bonds in MPTS and types of bonds in organic and inorganic part was obtained. Raman spectroscopy proved its considerable potential in technological process diagnostics. A molecular structure of components can be con-trolled at relevant stages of the synthesis. This is necessary in order to design new materials on a molecular level and obtain required properties and good quality of the final product.

11

Optical properties of electron beam deposited lutetium oxide thin films

Wiktorczyk T

Optica Applicata

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2001

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Vol. 31, nr 1

83-92

EN

Lu/sub 2/O/sub 3/ thin-film coatings of a thickness 0.1-1.3 mu m were deposited onto quartz plates by an electron beam gun. Optical measurements were carried out for the wavelengths lambda =0.2 mu m-2.5 mu m. All fabricated coatings were highly transparent in the spectral range from 0.3 mu m to 2.5 mu m. Optical constants of Lu/sub 2/O/sub 3/ films have been determined from the spectrophotometrically measured transmittance. The dispersion n( lambda ) and extinction k( lambda ) curves in the spectral range considered have been presented and analysed. The refractive index for Lu/sub 2/O/sub 3/ films has been estimated as 1.84 at 0.55 mu m. The characteristics of the real and imaginary parts of the dielectric function epsilon *(v) are also presented. Values of epsilon '/sub infinity /=323-3.53 have been obtained as the high-frequency optical relative permittivity for Lu/sub 2/O/sub 3/ thin films.

12

Model examination of the crossover effect in two-layer light-sensitive system

Latacz L., Nowak P.

Optica Applicata

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2001

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Vol. 31, nr 1

177-184

EN

The results of computer simulation of the effect of light scattering in a system composed of two heterogenic light-sensitive layers coated on two sides of a transparent base are presented. It has been assumed that the modelled system is irradiated with a directed X-ray beam, while the photographic effect is caused only by the light emitted by the fluorescent screens adjacent to the light-sensitive layers and containing phosphors fluorescing due to X-ray irradiation. The scattered light transpassing the base reaches the opposite light sensitive layer, thus damaging the sharpness of the details. This effect called crossover is disadvantageous in roentgenography. The qualitative dependence of the modulation transfer function of the system on both its geometric and optical parameters was examined. It has been shown that worsening of the image is the stronger the thinner the light-sensitive layers and the weaker the light scattering by single silver halide crystals. This result is surprising since in the case of single-layer light-sensitive systems not suffering from the crossover effect opposite effects are observed.

13

Model examination of application of fluorescent substance to silver halide light-sensitive layers

Latacz L., Nowak P.

Optica Applicata

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2001

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Vol. 31, nr 1

165-175

EN

The results of computer simulation of the outcomes of scattering, fluorescence and absorption of actinic light inside the hypothetical light-sensitive layer containing the silver halide crystals and fluorescent substance are presented. It has been assumed that the modelled layer is exposed exclusively to the radiation of the wavelength belonging to the intrinsic sensitivity range of silver halide. The quantitative dependence of the effective light absorption by the silver halide on the fluorescent substance concentration, the layer thickness, quantum efficiency of fluorescence and the ratio of the absorption probability of a photon of wavelength belonging to the sensitized sensitivity range and the absorption probability of a photon of the wavelength from the intrinsic sensitivity range has been examined. Also, the dependence of the modulation transfer function curve on the above parameters has been studied. The results obtained indicate that under some circumstances an addition of fluorescent substance can enhance the photosensitivity of the layer and improve simultaneously the sharpness of the recorded image.